External chill means for metal castings



0CL 17, 1944. H BQWSHER 2,360,392

EXTERNAL CHILL MEANS FOR METAL CASTINGS Filed Dec. 21. 1942 PatentedOct. 17, 1944 EXTERNAL CHILL MEANS FOR METAL CASTINGS Lawrence H.Bowsher, Lima, Ohio, assignor to The Ohio Steel Foundry Company, Lima,Ohio, a

corporation of Ohio Application December 21, 1942, Serial No. 469,667

1 Claim.

This invention relates to the making of metal castings, and particularlyto means for chilling castings, especially those of steel, at points oralong areas where the metal is of greater mass and the cooling thereforeretarded relative to adjacent portions of less mass.

It is well known in the metal casting art that in the making of angularmetal castings, external chilling members must be provided in contactwith the cast metal in reentrant angles and also in opposition to suchangles to prevent unequal cooling and the strains and stresses in thecastings resulting therefrom. These chilling members have customarilyconsisted of more or less round bar-like members within the angles andflat straight edged members against opposing surfaces. It is found,however, in practice that with the use of these straight edged memberscracks usually occur in the casting along the line or lines where thestraight edges of the chill members have contact therewith.

The object of the invention is the provision of chilling means of theclass described which is of a character and construction to prevent orreduce to a minimum the stress forming tendencies in castings, asabove-noted.

A further object of the invention is the provision of a. chill memberfor use in connection with metal castings, which member will have itsmetal contacting edges of serrated form to provide a plurality ofnarrowly spaced fingers at such edges with the fingers of graduallyincreasing thickness from their free ends inwardly, whereby a straightline chilling effect is avoided and a more efficient distribution of thestresses set up during cooling obtained.

The invention is fully described in the following specification, and apreferred embodiment thereof illustrated in the accompanying drawing, inwhich Figure 1 is a vertical cross-sectional view of a mold having aformed casting therein and equipped with chill members embodying theinvention; Fig. 2 is a perspective view of a casting removed from a moldand with the chill members still in attachment thereto, and Fig. 3 is aperspective view of one of the chill members used in connection with areentrant angle of the casting.

Referring to the drawing, I designates a cast article disposed in thecavity of a mold 2 in which it was formed. The chill members embodyingthe invention are designated 3 and 4 and are imbedded in the sand wallsof the mold in cooling engagement, at their exposed or mold cooling.

The chilling members 3 and 4 are of elongated bar-form and of across-sectional shape to fit against the surface of the casting to whichapplied. In the present instance, the member 3 is suitable to fitagainst the substantially flat top side of the casting over the heavyportion thereof, while the members 4 are suitable to fit in thereentrant angles in opposition to the member 3.

Each chill member 3, 4, includes a lengthwise extending body part 5 ofsufiicient volume to have the desired chilling effect on the portion ofthe casting metal against which disposed, and each side edge of suchbody part throughout its length is provided with a series of narrowlyspaced integral fingers 6 for full engagement throughout their exposedsides with the casting. These fingers are tapered substantiallythroughout their lengths to gradually increase their thicknessesinwardly from their outer ends and with the outer sides of each relativeto the casting inclined or receding therefrom. It is found in practicethat the best results are obtained by having the Width of the fingers 6and of the spaces 1 therebetween of substantially the same width withtheir walls parallel or substantially so. Each chill member is providedwith the usual spuds 8 to hold it in the sand wall of the mold.

The use of chill members of bar form the same as those illustrated,except that the side edges are straight or not serrated as shown, isold. It is found, however, that with the use of such straight edge chillmembers cracks occur and weakness develops or is present in the castingalong or adjacent to the straight lines which register with thesideedges of the chill members. It has also been found that by breaking upthe straight edge lines of the chill members so that they are serratedto provide a plurality of fingers, which are preferably tapered, the0bjectionable straight line chilling effected is avoided and thestresses set up in the casting during cooling are distributed in amanner to prevent cracks and weakened lines in the casting.

I wish it understood that my invention is not limited to any specificconstruction, arrangement or form of the parts, as it is capable ofnumerous modifications and changes without departing from the spirit ofthe claim.

Having thus described my invention, what I claim as new and desire tosecure by United States Letters Patent is:

A chill member for use in engagement with metal castings when beingformed to expedite the chilling of the contacting portion thereof,

